In three-dimensional (3D) computer graphics, a 3D model is a mathematical representation of a three-dimensional surface or object. A 3D model can be displayed as a two-dimensional (2D) image through 3D rendering. A 3D model can represent a 3D surface or object using a collection of points in 3D space, connected by various geometric shapes such as triangles, lines, curves and so on. 3D models are widely used in 3D graphics on personal computers and other devices in a wide variety of applications including but by no means limited to computer gaming. For example, computerized 3D models are used in the medical industry, in simulators, in movies, to represent chemical compounds, for architectural and landscaping uses, in engineering and for geological models, to name just a few.
Texture mapping is a method for adding detail, surface texture or color to a computer-generated graphic or 3D model. A texture map can be applied to the surface of a shape or polygon. Each vertex in a polygon can be assigned a texture coordinate either by explicit assignment or by procedural definition. Image sampling locations can be interpolated across the face of a polygon to achieve a more realistic appearance. Multiple textures can be applied to a surface. For example, applying a light map texture may be used to light a surface instead of recalculating the lighting each time the surface is rendered.